<?php
interface DAOInterface {
	
	/**
	 * add the object to database
	 */
	public function add();
	
	/**
	 * delete the object from database
	 */
	public function delete();
	
	/**
	 * update the object in database
	 */
	public function update();
	
	/**
	 * get all object of this class from database  
	 */
	public function getAll();
}
?>